The following function can be used to apply the gift certificate to the sales order through script
function applyGiftCertificateToSalesOrder(salesOrderId, giftCertificateCode, amountApplied) {
try {
let salesOrder = record.load({
type: record.Type.SALES_ORDER,
id: salesOrderId
});
let lineCount = salesOrder.getLineCount({
sublistId: 'giftcertredemption'
});
log.debug({
title: 'Line Count',
details: lineCount
});
salesOrder.setSublistValue({
sublistId: 'giftcertredemption',
fieldId: 'authcode',
line: lineCount,
value: giftCertificateCode
});
salesOrder.setSublistValue({
sublistId: 'giftcertredemption',
fieldId: 'authcodeapplied',
line: lineCount,
value: amountApplied
});
let updatedSalesOrderId = salesOrder.save();
return updatedSalesOrderId;
} catch (e) {
log.error({
title: 'Error Applying Gift Certificate',
details: e.message
});
throw e;
}
}